Cutting machines with means for automatically disabling the cutting drive and reducing the pressure of the clamp drive during replacement of the blade



June 7, 1960 R. HAYWOOD 2,939,357

CUTTING MACHINES WITH MEANS FOR AUTOMATICALLY DISABLING THE CUTTINGDRIVE AND REDUCING THE PRESSURE OF THE CLAMP DRIVE DURING REPLACEMENT OFTHE BLADE Filed Dec. 19, 1957 2 Sheets-Sheet l I6 FIG-l lNVENTOR RUSSELI. HAYWOOD 95 70 60 62 ATTORNEYS l. HAYWOOD ANS FOR AUTOMATICALLY DISJune 7, 1960 2,939,357 ABLING CUTTING MACHINES WITH ME 4 THE CUTTINGDRIVE AND REDUCING THE PRESSURE OF THE 19 l9CLAMP DRIVE DURINGREPLACEMENT OF THE BLADE 2 Sheets-Sheet 2 Filed Dec.

FIG-5 by Why Mi-O I44 I45 M i T CLAMP-1P DOWN INVENTOR. RUSSEL I.HAYWOOD 2 B U MW 1 A MWMVIM. 4 w J mm Cu fl\ M ATTORNEYS United StatesPatent CUTTING MACHINES WITH MEANS FOR AUTO- MATICALLY DISABLING THECUTTING DRIVE AND REDUCING THE PRESSURE OF THE CLAlVIP DRIVE DURINGREPLACEMENT OF THE BLADE Russell 1. Haywood, Dayton, Ohio, assignor toHarris- Intertyp'e Corporatlon Cleveland, Ohio, a corporation ofDelaware Filed Dec. 19, 1957, Ser. No. 703,787

6 Claims. (Cl. 83=-380) This invention relates to machines for cuttingpaper and like material and more particularly to a paper cutting machinehaving safety circuits which prevent operation of the cutting mechanismwhile the knife blade is being replaced.

In relatively large, power operated cutting machines capable of cuttingthrough stacks of sheet material, it is necessary to replace the knifeblade after it becomes dulled from use over a period of time. Since thisknife is heavy and somewhat awkward to handle, it is preferable forsafety reasons to have some means to raise and lower the knife intoposition without unnecessarily risking injury to the operator. Also, itis desirable that the cutting mechanism be positively stopped fromoperating during the time the operator is replacing theknife toeliminate any possibility of the machine being accidentally actuated andpossibly injuring the operators hands or arms. A hydraulically operatedclamp is used to hold the material in position for cutting by the knife,and is usually employed, while operating slowly under comparatively lowpressure, as a lift device for lowering the dulled knife and raising anew one into position for securing to the knife operating mechanism. i a

It is therefore a principal object of this invention to provide amachine for cutting sheet materialsuch as paper in which supportingmembers are provided for attachment to the clamping member to supportthe knife blade and to deactivate the knife operating mechanism so thatno accidental operation can take place.

It is another object of this invention to provide a machine for cuttingsheet material such' as paper and the like in which the knife operatingmechanism is positively locked in inoperable position during replacementof the knife blade.

Another object of this invention is to provide in a machine for cuttingpaper and the like electrical control means that are interrupted duringthe changing of the knife to'prevent the application of operating forcesto the knife operating mechanism.

A further object of this invention is the provision of a machine forcutting sheet material of paper and the like having'a clamp which isoperable only-under relatively low hydraulic pressure when the cuttingmechanism is rendered inoperable.

Other objects and advantages of this invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

In :the drawings:

'Fig. 1 is a schematic. front-elevation of a cutting machine accordingtothe invention showing the control panel with the knife supportingmembers stored therein;

. Fig. 2 is a schematic side elevation of the apparatus of.Fig..1showing the relative positioning of'the knife bladelandfthe clamp;

,Fig. 3 is .an enlargedfragmentary view of the knife bladefandthe clampwith the supporting members in position to receive the knife, the dottedportion indicating the position of the clamp when the knife is removed aReferring to the drawings, which disclose a prefer-red embodiment of theinvention the cutting machine comprises a base 10 having integral sideframe members 11 and 12 respectively, providing mountings for variousoperating parts of the machine. A work table 15 is supported on theframe, overhanging the frame at the forward or operators side andproviding a suitable support for receiving the material to be cut.

Front guides 16 and 17 are mounted to form guide channels merebetweenfor guiding and directing the movement of knife bar 20. A tie piece 21joins the guide members at their upper ends and extends across theentire width of the machine providing additional strength and rigidity.

The knife bar 20 has pads or guide surfaces 22 formed thereon at eitherend, parts of which travel in the spaced guides formed by members 16 and17. The knife bar has a bevel at its lower side as shown at 25 (Fig. 2)to which the cutting knife blade 26 is secured by means of bolts 27recessed into the knife bar.

The mechanism for actuating the knife is such that the cutting forcesareapplied substantially within the plane of movement of the knife bymeans of a simple arrangement of links and levers, giving a high rate ofknife movement and at-the same time avoiding lateral thrust on the knifeblade or on the knife bar which would interfere with uniformity ofcutting or result in unnecessary or excessive wear. a

For this purpose downwardly extending arms 30 and 31 are formed atopposite ends of the knife bar, these arms being apertured to receivepins 32 and 33 therein, and the pins being mounted, as shown, adjacentand approximately in the plane of the lower edge of the.

knife. The connections for the opposite ends of the knife are arrangedto provide a double shear operation. That is, the knife moves downwardlyand laterally during the cutting stroke, but since the opposite ends ofthe knife are at different initial elevations above the cutting table,one end moves downwardly to a greater extent by means of pin 37 to onearm of a three arm bell crank 40 which is pivotally mounted in the frame11 for rotation about the axis of pin 41. A suitable projection at theread side face of the knife bar travels in the guideway 42. a e

The oppositeend. of the knife bar is connected by means of link 45 topin 33, such link having an adjustable threaded connection 46 by meansof which its efl:'ec-. tive length can be varied. At its lower end link45 is secured by pin 47 to one arm 48 of a two arm bell'crank49pivotally supported in frame 12 by means of pin 50,

Patented June 7, 1960 This link has an adjustable. threaded connection36 by means of which its length can be changed, and its lower end ispivotally connected A sseeadsrm s1 erasures bell crank '40 receives apin52 which secures a cross bar 55 thereto, this bar having a pivotedconnection as shown at 56 with the lower arm 57 of the two arm bellcrank. Thus, as shown "in Fig. l, the two bell cranks are caused toswing in unison through thecross bar 55, each bell crank causing theactuation of a corresponding end of the knife her through a difierentpath of movement by bringing its associated end of the bar into ahorizontal position at V the limit of its down stroke,

The operation of-the knife bar 20 is effected by means of a connectingrod 60 attached to the third arm 61 of the three arm bell crank 40. Theconnecting rod is driven from a crank pin 62 carried on crank plate 63suitably mounted in the lower frame of the "machine.

The drive mechanism is shown in Fig. 4, where the main shaft 65 is shownas rotatably' supporting the crank plate 63. l i

wheel 68511155 gear assembly being mounted for rotation on astationary'shafit 70. Gear wheel 68 is driven from a pihion 71 mountedon a counter shaft- 72 which is V rotatably supported in theframe-of themachine.

Power is supplied from a drive motor 75 located at the rear of themachine and, for convenience, supported on-the rearwardly extending endof the fixed shaft 70. The motor has a drive pulley 76 over whichoperates a plurality of V-belts '77 which frictionally engage the outercircumference of a flywheel 80, transmitting driving torque thereto.Flywheel 80 is carried on ashaft 81 which-thus serves as 'a drive shaft,being coaxial with,

but spaced fiforn counter shaft 72.

Clntch; and brakemechanisms l V trolling the interconnectionof. thedrive shaft 81 and counter shaft 72, the clutch 'beingshown at 82 andthe brake being indicated at 8 3. The clutch is electromag- V netso thatit can be engaged bybfiergization of its wind-' lugs to operate thecutting mechanism any time power is. supplied to the machine.

fAlso secured to main shaft 65 isja. cam' shaped safety 7 plate'85-which rotates with, the shaft. A safety 'latch' p'in 86 is arrangedto project into the path of travel of plate 85 and interfere withfunther rotation thereof should there be a malfunction in' the machinesoperating.

mechanism. 'As noted, the safety latch is operated by means of-asolenoid 87 enabling latch 86 to be auto "mat'ically withdrawn fromprojection into the path 'of' plate 85 upon 'e'nergization of 'motor 75a cuttin'gl'or tfimming relatively thick stacks or piles ofpaper'materials it is essential that the stack be held afiiredpositionduring the operation of knife bar 20 so that-the sheets will'all be of:the same dimensions with n no torn or "ragged'edges. Accomplishment ofthispurpose is normally achieved by a clamp 90 which reciproare providedfor con-' wise power is available for raising the clamp to its elevatedposition above the work material on-the table.

The hydraulic system providing for operation of clamp 90 is shown inFig. 7 where hydraulic cylinder 105 with piston 106 is shown indiagrammatic form. Hydraulic pressure is created within the hydraulicsystem by means of pump 110, the pressure developed by'thepump within Ithe system being determined by means'of relief valve 111 which has oneside co nnected to'a lower pressure Shaft '65 rotated by a gear 66secured thereto and" operated by a pinion 67 which is secured to a largegear return system; or tank T. A valve 112 and a pressure gage 113 havebeen operably connected to the hydraulic circuit by conduit 114 whichtaps into the conduit 1 15.

co'nnecting'the' pump 110. with relief valve 111. Placed within thefluid conducting system between the fluid pump and hydraulic cylinder105 is a check valve 116 which prevents reverse flow'of fluid toward thepump and a pair of flow control valves 120, 121 which are connected inconduits 1'22, 123, the latter two conduits connecting the hydrauliccylinder with a reversing valve 125.

The valve 1'25 is operated by a solenoid 126 to determine the directionof fluid flow through the valve for up "and down movement of piston106." The valve as shown in the drawings is in a position causingfiow'of hydraulic V fiuid into the top of cylinder 105 so that the'fluidcontained in the bottom of the cylinder is escaping through v conduit .123 to tank T for recycling by 'pumplllll.

Since it is sometimes desirable for the clamp to be operable under arelatively low pressure as compared with the relatively high hydraulicpressure used when the clamp is holding a stack of material against theworking table,

an additional' hydraulic line 127 is provided in which a V dump valve130'is connected into the system; through a needle v'alve 1 3 1, andoperation of valve 130 is con-- trolled by means of a solenoid 132. Thepressures in cates toward and away from work table 15 adjacent the knifebar 20. The close proximity of knife bar 20 and clamp 90 is readily seen"by reference to Figs. 2 and 3.

Operation'of theclam'p is produced by means of parallel linkage such asshown'in detail in 'Patent No.'2,599,59 l. This linkageincludesdownwardly extending arms 91 ahd' belt-crank levers, 97,:98"respec'tively. Lever 97 is pivotally supported on "the A forward endof stationary shaft fwhileflever 98 ispivotally mounted on pin 1 00 sublysupportedfinside frame 1'2. V V

e'ba' '101 joins 'theoppositeends'ofthe bell 'cranks for correspondingmovement, and power is applied thrpugh alink 102 pivotally attached at103 to bellcr'ank' 98 A'hydr'aulic cylinder r05 having'a movable piston'sreia is pivotally attached to'the link 102 by means i107:thisfmechanis'm actuating power l-able o the lam to hold it 'in contactwith the rte be cut with "a preueter-mi ed rorc'e, and like- -l1'av'inglinks :19}, '94 "pivotally secured to their; 7 lower ends. rPins 9 5; 96secure the" links to the arms of the hydraulic system are so controlledthat'ther'e is at all times a minimum operating pressure in the mainline 115 sufficient to hold clamp 90in its uppermost position withoutassistance from any mechanical holding or loclc ing means. This lower orminimum pressure is maintainedfwhen replacement of aknife' blade 26'isto' be effected, since the operator is working directly withtheknifeduring this period of time andaccidental operation 'of the clampunder high pressure serious injuiy to the operator.

could result in Due to the inherent danger in cuttmg machines of thenature described/many safetyprecautions have been in-- corporated whenbuilding the machines to prevent -ac-* cidental operation of the knifeblade and to require that the operators hands and armsbe completelyremoved fromthe vicinity oftheknife blade b'efore operation can takeplace. An example of'onesuc'h safety device is the safety latch 86mentioned earlier. Obviously when a a blade becomes sufficientlydulledthat it needs replacement the operator must handle the heavyawkward blade,

position such that the supporting 'members'135 are im- -rriediatelybeneath the blade to provide support. Such an arrangement is indicatedin Fig. 3 wherein the supporting members .135 are shown in the positionthey would asslime during the removal of blade '26from knife bar 20.

If the knife driving mechanism were to be actuated when the supportingmembers are "threaded into clamp 90, a great deal of damage could bedone to the cutting and clamping mechanisms, and since the operator'shands are apt to be in the vicinity he could be -severely'injuried.

Therefore, the present invention provides an electrical circuit which istied in with thedfiving motor circuitand 182 and throw switches into aclosed position.

the hydraulic circuit to preclude the actuation of the cutting bar 20,and to permit the operation of clamp 90 under low hydraulic pressureonly.

Referring to Fig. 6 the power input lines L1, and L2 have a number ofparallel circuits extending therebctween. The first parallel circuitline 140 contains a suitable ofi-on main control 141, a control relay142 and one set of its relay contacts, 142a. This circuit 140 isinitially energized through line 143 by closing the series connectedswitches 144 and 145 therein. The line 143 provides a by-pass for relaycontacts 142a until such time as the relay 142 is closed, therebyclosing the contacts and loci-.- ing the circuit into operation. Circuitline 146 is normally open until series connected switches 147 and 148are closed to complete the circuit through a normally closed clampcontrol switch 149, a second set of relay contacts 142b, and a secondcontrol relay 150. Upon closing of control relay 150 its relay contacts150a in line 151 are closed to by-pass switches 147 and 148 and lockthis circuit into operation. A third circuit line 155 is energized uponthe closing of control relays 142 and 150 (which close their respectiverelay contacts 1420, 15%), and series connected switches 156, 157, theselatter switches being closed simultaneously with switches 147, 148 andopening of switches 144 and 145.

Also contained in line 155 is a second pair of series 7 connectedswitches 158, 159 energization of which causes actuation of clutch 82.Connected in parallel with the three prior circuits is a circuit line165, which has relay contacts 150a controlled by a relay 150, so thatthis circuit will not be energized'until circuit v146 is also energized.Upon closure of contacts 150a energization of the solenoid 126 occurs tothrow valve 125 into a position causing fluid pressure to be supplied tocylinder 105 through conduit 123 to force piston 106 upwardly causingdownward movement of clamp 90. 7

Circuit line 170 also extends between power input lines L1 and L2 and itcontains a pair of series connected switches 158a, 159a which areoperated simultaneously and in unison with switches 158, 159 so that thesafety latch solenoid 87 will also be deenergized. The safety latch 86then cannot be withdrawn and movement of the knife bar operatingmechanism is prevented. To insure that solenoid 87 cannot be accidentlyenergized, circuit 170 includes relay contacts 150d, thus requiring thatcontrol relay 150 be closed before solenoid 87 can be energized towithdraw safety latch 86 from engagement with safety plate 85. A finalcircuit line 175 is joined to circuit 170 on the output side ofswitches158a, 159a so that opening of these switches will causeinterruption of solenoid 132 which controls the operation dump valve130. When this solenoid is deenergized the dump valve is arranged toprovide only a low hydraulic operating pressure to clamp 90.

The switches 158, 158a, 159, 159a are present in the form of doublepole-single throw switches located within a control box 180 (Fig, l)which is secured to the front of the cutting machine. During normaloperations the supporting members 135 are stored in control box 1 80 sothat the ends will force against the contact buttoms 181, While thecircuits 155, 170 are illustrated as being interrupted upon removal ofthe knobs or supporting members 135 from box 180 through opening of thedouble pole-single throw switches, it is possible for other circuitinterrupting means to be used in conjunction with supporting members135.

When replacement of a knife blade 26 becomes necessary the operatorremoves supporting members or knobs 135 from control box 180 thusinterrupting the two electrical circuits 155 and 170, deenergizingsolenoids 87 and 132. With deenergization of circuit 155 the clutch 82cannot be used to connect motor 75 to main shaft 65 and effect operationof the cutting mechanism. Concurrent with removal of the clutch from theoperating circuit, both solenoids 87 and 132 are deenergized so thatknife safety latch 86 cannot be withdrawn from locking engagement withplate and dump valve is opened to reservoir or tank so that only the lowoperating pressure is available to clamp 90.

Once removed from control box 180, knobs 135 are placed on clamp 90,after it has been lowered under the lowv pressure to its lowermostposition and clamp switch 149 thrown to open circuit 146 and deenergizethe control relay 150. This opening all of the relay contacts 150a-d.The opening of relay contacts 150:: removes solenoid 166 from thecircuit and reverses valve 125 to cause flow of hydraulic fluid, throughconduit 122 into cylinder 105 and through conduit 123 from cylinder 105.Thus piston 106 moves into cylinder 105 and the clamp 90 moves upwardlytowardcutting bar 20.

The upward movement of the clamp is continued until supporting members135 reside just beneath knife blade 26, as shown in Fig. 3, so that thebolts 27 in the knife bar 20 can be safely and easily removed withoutany fear that the blade will drop and injure the operators hands or armsOnce the old blade has been removed a new one can be substituted, thesupporting members 135 are returned to control box where they will closeswitches 158, 158a, 159 and 159a, and thus the electrical and hydrauliccircuits, are restored. Additionally, when the supporting members arestored within the control box they will always be readily. availablewhen needed.

While the form of apparatus herein described constitutes a preferredembodiment of this invention, it is to be understood that this inventionis not limited to this precise form of apparatus and that changes may bemade therein without departing from the scope. of the invention which isdefined in the appended claims. 7

What is claimed is:

1. In apaper cutting machine having a removable knife blade and anadjacenthydraulic motor operated clamp for holding a pile of sheetmaterial in position for cutting and including a member attachable tothe clamp for temporarily supporting the knife blade while effectingreplacement thereof, the combination comprising a hydraulic circuitincluding control means providing relatively high and low operatingpressures to the clamp motor for actuation thereof under high and lowpower selectively, driving means for actuating said knife on a workingstroke, an electric circuit including first means for operating saidknife blade and second means controlling the hydraulic pressure suppliedto said clamp, switch means connected in said electrical circuit tocontrol the operation of said first and second means, and means mountingsaid switch means on the cutting machine for operation by saidsupporting member to cause disabling of said driving means and operationof said control means to provide low pressure only to the clamp motorwhen said supporting member is attached to said clamp for use insupporting said blade thereon during replacement thereof.

2. In a machine for cutting sheet material, the combination comprising awork table for receiving a pile of sheet material, cutting meansincluding a replaceable knife blade movable toward and away from saidtable for cutting said material, clamp means adjacent said cutting meansfor holding said pile in position on said table while said cutting meansis operating, a supporting member attachable to said clamp forsupporting said blade during replacement thereof, a hydraulic circuitincluding means providing relatively high and low operating pressures tosaid clamp means for actuation thereof, driving means including aselectively controlled clutch therein connected to actuate said cuttingmeans, an electric control circuit including means controlling actuationof said clutch, means in said circuit for controlling the hydraulicpressure supplied to said clamp, a control box on said machine includinga storage place for said supporting member, switch means operablyconnected to control the supply of electrical power to said electriccircuit, and means supporting said switch means within said. control boxinlposition for actuation in response to presence of said supportingmember to alter the power supply to said; cir-f cuit to'cause thedisabling of" said driving means when. said supporting member is removedfrom said control box and mounted on'said clamp and to preventapplication of high pressureto said clamp means, 1

3 In 'a paper cutting machines includingsa removable reciprocable knifeand an adjacentv hydraulically operated clamp for holding a pile ofsheet material in position for" cutting by the..knifeand including alsoa support member attachable. to. the clamp for temporarily supportingthe knife while effecting replacement thereof,-the combination ofdriving means for said knife, separate hydraulic driving means for saidclamp, selective means establishingrhigh' 7 and low hydraulicpowersupplies for said clamp driving means, means on said machine defining astorage station for said support .member, control means, adjacent .saidstorage stationflresponsivetto presence of said member at said stationto, actuate said selective means to establish said highpower supply forsaid clamp driving means and also to providepower for saidknife drivingmeansfand said. control means being responsive to removal'fof saidvsupport member to actuate said selective means to establish and maintainsaid low power supply fortsaid clampi driving meansfand also to maintainsaid knife'driving' means in a disabled condition. 1

4.1 In afpaper cutting machines including-a removable reciprdcable knifeand anadjacent clamp for holding a pileofsheetrnaterial in position forcutting bythe knife. and including also a support member attachable'tothe; clamp for temporarily supportingthe knife while eifect-f 7ingreplacemen't thereof, the combination of driving means for saidknife, separate driving means for saidrclamp, 'selectivetme'ansestablishing high and lowrpower supplies meansadjabent said storagestation connectediwith said seleetivejmeans for operation, bysaidsflpPQtt memberv in' said storage station to'actuate said selectivemeans to establish said high power supply for said clamp driving means,and also ,to provide power for said knife driving for said.clampfldriving means, means on saidmachine 6 defining a storage stationfor saidfsupport membencontrot means, and saidl'control means beingresponsive to; ree 45 moval of said support member fromv said storagestationto estaolishsaid; low power supply for said clamp driving meansandalso to disable said knife driving means.

Sgln apapercutting, machine including a removable reciproeable knife andan adjacent clamp for holding a;

8: pile of sheet material in position for cutting, by the knife andincluding also a support member attachable to the clamp for temporarilysupporting the knife while efiect-V ing replacement thereof,- thecombination of driving means operative to reciprocate said knife inresponse to 'selective control thereof, separate selectively operabledrive means for said clamp, selective means establishing high and lowpower supplies for said clamp driving means, latch means operative toprevent reciprocation of said knife and including afcontrol: thereforoperable with said knife driving means'to release said latching meansduring 'a deliberate operation of said knife, means on said machinedefining a storage station forsaidfsupport member, control meansconnected to actuate said selective means to establish said highpowersupply for said clamp driving' means and also to providetpower forsaid knife driving means,;and a member in said control means responsiveto transfer of said support memberrfrom said storage station to saidclamp ,for'actuating said control means to establish said low powersupply for said clamp driving means and also to disable said knifedriving means and prevent release of, said latch means,

6; In a paper cutting machine including a removablereciprocable,knifenand an adjacent clamp for holding a pile ofsheetmaterial in position for cutting .by the knife and including alsoasupport member attachable to the. clamp for temporarily supporting theknifewhile eflecting 'replacementthereof, the combination of drivingmeans operative to reciprocate'said knife in response to selectivecontrol thereof, separate selectively operable drive means for saidclamp, selective means establishing high and low power supplies for saidclamp driving ,rneans, means on said machine defining a, storage stationReferences Cited in the file of this patent UNITED STATES PATENTS"1,743,946 Williams-Ha Jan; 14, 1930 2,578,317 Pealer Dec. 11, 19512,713,407 Miller July 19, 1955 i i i

